Color couplers containing terphenyl radicals



Patentcl May 1, 1351 COLOR COUPLERS CONTAINING TERPHENYL RADICALS Charles F. H. Allen, Rochester, N. Y., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application March 2'7, 1947; Serial No. 737,713

12 Claims.

This invention relates to color photography and particularly to color-forming compounds for color photography.

The use of color-forming compounds which react with the development product of primary aromatic amino developing agent to form colored images on photographic development is well known and has been the subject of numerous prior patents. The dyes formed in this way are insoluble in water and in the ordinary photographic developing and fixing baths, although the silver images formed simultaneously with them during the photographic development may be removed from the photographic layer to leave pure dye images in the layer. The coupler compounds employed in this way may be added to the developing solution or in certain cases may be incorporated in the photographic layer prior to exposure. When the coupler compounds are incorporated in the developer solution, it is desired that they be sufficiently soluble in the developer solution so that amounts may be used which produce sufficiently high dye densities in the resulting photographic image. One of the difficulties encountered when color-forming compounds are incorporated in a photographic emulsion is the tendency of the coupler to crystallize in the emulsion. This produces excessive graininess.

It is therefore an object of the present invention to provide novel photographic coupler compounds having desirable color-forming properties. A further object is to provide coupler compounds which may be incorporated in a photographic emulsion which is part of a multi-layer coating and which do not diffuse from the emulsion in which they are incorporated. Other objects will appear from the following description of my invention.

These objects are accomplished by incorporating in the usual coupler molecule a terphenyl radical, especially an o-terphenyl radical. The preparation of o-terphenyl and some of its derivatives have been described by Allen and Pingertin Journal of the American Chemical Society, vol. 64, pages 1365 and 2639.

The couplers which we propose to use may have the following structural formula:

where R, represents a nitrogen or carbon atom connected to, or part of, a coupler molecule containing a reactive methylene or a reactive phenolic methenyl group. The reactive methylene groups ordinarily encountered in color couplers are those of the structure The phenolic methenyl groups usually encountered in coupler molecules are those of the phenolic or naphtholic hydroxyl type having a reactive position para to the hydroxyl group, that is, a position which is unsubstituted or which is substituted with a replaceable group. In the general formula above, the terphenyl radical may contain other substituents. The general formula illustrates the structure of o-terphenyl but I may also employ other terphenyl radicals such as mterphenyl and p-terphenyl as illustrated in the specific examples below..

The following examples illustrate compounds which may be used according to my invention and the method of preparing them.

1. 1-[4'-(o-terphenylyll-ZS-amino 5 pyrazolone One part each of hydrazino-o-terphenyl and ethyl p-ethoxy-p-iminopropionate are added to 10 parts of ethyl alcohol, the mixture is heated to boiling, and /3 part of glacial acetic acid is added; the mixture is refluxed for '2 minutes, and. cooled to room temperature. A freshly prepared solution of sodium ethoxide /5 part of sodium dissolved in 6% parts of absolute ethyl alcohol) is added to the solution. The alkaline solution is refluxed for 30 minutes; it is then cooled to room temperature and acidified with 2% parts of glacial acetic acid. If no precipitate separates in 30 minutes it is seeded with a previously prepared sample. The solid is filtered ofi after 2 hours, and washed with alcohol and water. The yield of the aminopyrazolone. M. P. 215-220, is part. For purification one part of the crude pyrazolone is crystallized from 45 parts of alcohol to give 0.5 part of lustrous, tan-colored plates, M. P. 223-225.

2. 1-[4'-(o-terphenylyl) l-3-benzamido-5 pyrazolone' on the steam bath, it is then poured into 50 parts of 5% hydrochloric acid. The aqueous solution is decanted from the gum which separates. The phenyl-3-amino-5-pyrazolone and 3 parts of v gum is rinsed with water and then dissolved in terphenyl-l-carboxy chloride in parts of Xyparts of 5% alcoholic-potassium hydroxide, aflene under a reflux condenser for 0.5 hour. ter 5 minutes the alkaline solution is acidified to The diacyl compound which resulted was parlitmus with acetic acid; the tan colored solid 5 'tially saponified at room temperature with al which separates is washed with alcohol, water coholic potassium hydroxide. The monoacyl and again with alcohol, and dried at 100. The compound was precipitated by acetic acid. It reyield is 1 part of the benzamidopyrazolone, M. P. crystallized from acetic acid, forming a crystal- 228-230 The crude material can be crystallized line powder, M. P. ISO-181. from ethanol or from acetic acid to give a product 5. 1 p (p' tert. butylphenoxy) phenylwith melting point of 234-235". 3 (x' chlorosulfonyl o terphenamido) -5- 3. l-(p-cyanophenyl)-3-(o-terphenyl-4 car- (x-chlorosulfonyl-o-terphenoxy)-pyrazole N=CNHCO Q t-C Ho -o- N\ SOICI 1 bamido) -5-pyrazolone This coupler was prepared by condensing one mole of 1-p-(p'-tert.-butylphenoxy)phenyl-3- N=C-NHCOC amino-5-pyrazolone and two moles of 4'-carboXy-x-sulfo-o-terphenyl dichloride in boiling H anhydrous ethyl acetate. The product was ob- 2 O tained as a light tan powder on removal of the solvent.

Four parts of l-(p-cyanophenyl) -3-amino-5- pyrazolone is suspended in 100 parts of dry dicxane and at room temperature with stirring 11.68 parts of o-terphenyl l-carboxylic acid chloride is added in about 5 minutes. When the initial rise in temperature has subsided, 5.16 parts of quinoline are added and the reaction mixture is stirred for 2 hours. The temperature, which at first reaches about 35 0., falls to about that of phenyl] naphtgg'mhde} the room.

Two hundred parts of cold water is added to the flask and stirring continued until the oily material first formed has solidified. The solid is filtered, washed several times with cold water 6 Calc. for omHiac zNaoa z I 111d 6. 1 hydroxy 2 {[4' (2" phenyl)-- and dried.

The dry material is suspended in 200 parts of alcohol and 2.9 parts of 40% sodium hydroxide solution is added to the suspension, and the reaction stirred for 2 hours at room temperature. Twenty-five parts of cold Water is added to the solution, the whole filtered if necessary,

This coupler was prepared by heating a mixture of equimolecular amounts of phenyl l-hydroxy-Z-naphthoate and 4'-aminoo-terphenyl at 150-160" for 10 minutes. The productrecrystallized from alcohol in rods; M. P. 180-181".

and neutralized with 2.7 parts of acetic acid. The solid formed is filtered, washed with water and ifi gg Found dried. After crystallization from 25 parts of alcohol, the product melts at 255-257" C. C 8385 8261 i. 1 [p (p' tert. butylphenoxy) -pheny1l- H -3- (4 -o-terphenamido) -5-pyrazolone /N=CN1E IC o.

l E O This coupler was prepared by heating a mix- '7. 1 hydroxy 2 {p [4. (4 o terture of 1.6 parts of l-p-(p'-tert.-butylphenoxy) phenamido) l-phenethy1}-naphthamide This coupler was prepared by the condensation below 50 C. of l-hydroxy-Z-B-(4'-aminophenyl) ethylnaphthamide hydrochloride and o-terphenyl-4'-carboxy chloride in dioxane in the presence of quinoline. The product crystallized from glacial acetic acid in plates, M. P. 227-228.

8. 1 hydroxy-2-{B- [4' (x" chlorosulfonyl- 4-o-terphenamido) l-phenethyl}-naphthamide -o ONHCH CH -ONHC 0 C6150 OCH- C ONE A solution of 2.5 parts of ethyl benzoylacetate and parts of xylene in an open Vessel was heated by means of an oil bath maintained at 150-160". Then 2.45 parts (0.01 mole) of l-amino-o-terphenyl was added and the mixture was heated to gentle boiling for one hour. The solution was cooled to 70, 4 volumes of technical hexane was added and the mixture chilled. The crystalline product was filtered, washed with hexane and recrystallized from absolute alcohol (50 to 1). The yield of product, melting at 163- 164 C., was 2.55 parts (65%).

Alternatively the procedure described in Organic Syntheses, vol. 25, p. 7, for benzoylacetanilide may be employed.

10. By a similar procedure, 4-(o-methoxybenzoylacetamido)-o-terphenyl was obtained, using ethyl o-methoxybenzoylacetate. 149-150" C.

l1. 4-(benzoylacetamido-m-terphenyl) 061350 0 orno ONHQCo s This compound was prepared similarly to compound 9 from ethylbenzoylacetate and l -aminom-terphenyl. It had a melting point of 154- 155 C. 4-amino-m terphenyl is described in Journal of the American Chemical Society, vol. 64, page 2485 (1942).

12. 4-(benzoylacetamido-p-terphenyl) This compound was prepared similarly to compound 9 (from ethylbenzoylacetate and 4-aminop-terphenyl). It had a melting point of 262- 263 C. 4-amino-p-terphenyl is described in Journal of the American Chemical Society (1938), page 1364.

It melts at 13. x- (Benzoylacetamido) -2,3,6-triphenyl tolu ene came 0 01120 oNH 3 This compound was prepared similarly to compound 9 (from ethyl benzoylacetate and x-amino- 2,3,6-triphenyl toluene). It had a melting point of 193 194 C.

14. x (Benzoylacetamido) 4 n butyl o terphenyl CaHsO O CHzC ONH A mixture of 3 parts of ethyl benzoylacetate and 10 parts of xylene was heated to reflux and 2 parts of x-amino-4-n-butyl-o-terphenyl was added. The solution was heated at reflux for 1 hr. It was then concentrated in vacuo to give a yellow oil which coupled with 2-amino-5- diethylaminotoluene hydrochloride, in the presence of an oxidizing agent, to give a yellow dye.

The intermediates used in the preparation of the couplers described above were prepared as: follows:

4-n-butyryl-o-terphenyl c an,

A solution of 138 parts of o-terphenyl, 67 parts of n-butyryl chloride and 150 parts of ethylene dichloride was cooled to 10 and 87 parts of resublimed aluminum chloride added in portions with stirring during one hour. The mixture was stirred for four hours at 5 to 0 and decomposed with iced hydrochloric acid. The organic layer was removed, washed with dilute acid, mixed with Water and made almost neutral with sodium carbonate solution. The solvent was removed by steam distillation, and the residual oil extracted with 700 parts of ether. The ether solution was washed and evaporated. Distillation of the crude, fluorescent oil yielded parts of the ketone; B. P. 187-190 C. (1 mm.). It crystallized from methanol in hard, transparent prisms; M. P. 78 C.

Calcd. for C22H20O2 C, 87.9; H, 6.7. Found: C, 87.6; H, 6.7.

4-n-butyl-o-terphenyl Amalgamated zinc was prepared by treating 250 parts of mossy zinc with 300 parts of water, 25 parts of mercuric chloride and 12 parts of concentrated hydrochloric acid. To the zinc amal:

sew-mi gain thus obtained was added 35 parts of concentrated hydrochloric acid, 10 parts of acetic acid, and a solution of 50 parts of 4-n-butyryl-o-terphenyl in 100 parts of toluene. The mixture was heated under reflux for 24 hours; hydrogen chloride was passed in slowly during the first six hours. The: toluene solution was removed, washed and distilled. If necessary the distillate may again be subjected to the above treatment, using a fresh portion of amalgamated zinc. The product (34 parts) distilled at 165-167 C. (1 mm.), and crystallized from methanol in large, transparent prisms; M. P. 44 C.

Calcd. for C22H221 C, 92.3; H, 7.7. Found: C, 92.3; H, 7.7.

4 -n-butyZ-m-nitro-o-terphenyl Gem The nitration of 4-n-butyl-o-terphenyl (8.6 parts) was carried out in the manner described vfor 4-nitro-o-terphenyl distillation of the crude product yielded 6.7 parts of an intractible, yellow oil; B. P. 196-206 C. (1 mm.)

Calcd. for C22H21NO'2: N, 4.2. Found: N, 4.3.

:r-Amino-4-n-butyZ-o-terphenyl C aHn :from alcohol melted at 155.5 C.

Calcd. fOr C29H26N2O3Z N, 6.2. Found: N, 6.3.

4-nitro-o-terphenyl A solution of 115 parts of 95% o-terphenyl in 2250 parts of glacial acetic acid was heated to 55-60 C., and a solution of 25 parts of fuming nitric acid (d. 1.49) and 50 parts of red fuming nitric acid (d. 1.59) was added dropwise during one hour. The temperature was kept at 55-60 C. by regulating the rate of addition and by cooling when necessary. The reaction mixture was then heated at the same temperature for 6 hours, cooled, and poured into 1500 parts of water. yellow, semi-crystalline tar which formed was washed successively, by decantation, with warm water, sodium carbonate solution (400. parts) .and again with warm water. It was dissolved in 750 parts of ether and washed again with water, twice with 50 parts of 5% sodium carbonate solution, water and saturated brine. When the ether was evaporated the residue weighed 136 parts (99% crude yield). Crystallization from 1300 parts of 3A alcohol yielded 61 parts of product, melting at 108-1135 C. Recrystallization from 600 parts of alcohol gave 52.3 parts (38% yield) of 4-nitro-o-terphenyl, melting at 111-114 C.

The

Q 4-amino-o-terphenyl A hot solution of parts of 4-nitro-o-terphenyl (M. P. 111-114.) in 1600 parts of 3A alcohol was placed in a copper, low-pressure bomb of 4500 parts capacity. About 10 parts of Raney nickel and 5 parts of sodium carbonate were added, and hydrogen was introduced to a pressure of 50 lbs. The bomb was shaken and heated externally by steam until the absorption of hydrogen had ceased. It was necessary to introduce more hydrogen as the pressure dropped to 10-20 lbs. The hot reduction mixture was filtered by suction through a pad of Filter-Gel, the filtrate cooled to 0, and the product removed by filtration. The first crop weighed 75.4 parts; M. P. 117-118". Concentration of the filtrate to 300 parts gave an additional 41.8 parts (M. P. 1l6-1l7) for a total yield of 117.2 parts (94%).

4-acetyZ-o-terphenyl A solution of 138 parts of 95% o-terphenyl in parts of ethylene dichloride, and 50 parts of acetyl chloride was placed in a suitable vessel, equipped with a stirrer, condenser and thermometer. Then 8'7 parts of resublimed aluminum chloride was added in portions during one hour keeping the temperature below 0. When the addition was completed, stirring was continued for 2 hours; the mixture was then decomposed by iced hydrochloric acid, and the solvent removed by steam distillation. The residual oil was taken up in ether and washed successively with water, 5% sodium carbonate, water, saturated brine and then filtered. The product separated on concentration of the filtrate. Yield of 101 parts (6 M. P. 93.5-94.

4-carboxy-o-terphenyl A sodium hypochlorite solution was prepared by passing 111 parts of chlorine into a solution of 150 parts of sodium hydroxide in 225 parts of water and containing 450 parts of crushed ice. The temperature was kept below 0 during the addition of chlorine by an ice-salt bath.

The hypochlorite solution was added in a fine stream tQ-a warm solution of 90 parts of 4-acetylo-terphenyl in 1200 parts of methanol contained in a suitable vessel. The solution was stirred during the addition and considerable heat was evolved. Finally the mixture was heated under reflux for 5 hrs., cooled to about 5, filtered, and washed with water. The solid cake was dissolved in,900 parts of hot water and filtered. The hot filtrate was acidified with concentrated hydrochloric acid (about 30 parts required),

cooled, filtered, washed with water and dried.

Yield of the crude acid was 75-80 parts.

By concentration of the methanolic filtrate (from the first filtration) additional sodium salt 'give 68.4 parts of pure product. of the filtrate to 200 parts gave an additional was obtained, from which 18 parts more of the crude acid was recovered.

The acid was recrystallized from methanol to Concentration 11 parts for a total yield of 79.4 parts (87.7%) M. P. 202-203".

4-carbo-xy-r'-sulfo-o-terphenyl in 300 parts of tetrachloroethane was cooled to 10 and treated dropwise with 12 parts of redistilled chlorosulfonic acid in 35 parts of tetrachloroethane. overnight at 55-60 (3., cooled, and the filtered 01f, and rinsed with ether. The yield was 23 parts (66%) It can be crystallized from nitromethane, nitroethane, or chloroform, after which it has a melting point of 243-248.

4-carbomy-m'-suZfo-o-terphenyl dichloride CaH5 An intimate mixture of 19 parts of 4-carboxyx'-sulfo-o-terphenyl and 224 parts of phosphorus pentachloride, and protected from external mois- 7 ture, Was warmed on the steam bath, with occasional shaking, until the reaction had subsided. The liquid, which solidified on cooling, was broken up, decomposed by ice water and the acid chloride extracted with 650 parts of ether. After removal of the solvent under reduced pressure, 13 parts (62% yield) of the dichloride, M. P. 141-1492 remained. No suitable solvent for crystallization was found. It was characterized by conversion to the diamide, M. P. 272-277, which had the correct analysis.

4-hydrazino-o-terphenyl NHNHr filtered, suspended in ether and shaken with 30 parts of 5% sodium hydroxide solution until completely dissolved. The ether solution was washed, dried and evaporated to a small volume, and petroleum ether was added to precipitate 4.1 parts of the crude, cream-colored hydrazine (M. P. 118-124" C.). Recrystallization from alcohol raised the melting point to 123-125".

Analysis: Calcd. for CmHmNZ: C, 83.1; H, 6.2. Found: C, 82.7; H, 6.4.

A solution of 27 parts of 4-carboxy-o-terphenyl The mixture was then stirred product This compound was unstable and decomposed I over a period of a few weeks,

The coupler compounds of my invention may be incorporated in the photographic layer prior to exposure and the colored image formed by development of the layer in a primary aromatic amino developing solution. In the case of multilayer film, the color forming compounds may be incorporated in one or more of the emulsion layers. They may be incorporated in the emulsion as described in Mannes and Godowsky U. S. Patent 2,304,940, granted December 15, 1942, or J elley and Vittum U. S. Patent 2,322,027, granted June 15, 1943. Certain of the couplers may also be incorporated in the developing solution. When incorporated in the emulsion layer, the

5 exposed emulsion may be developed in the following developer to form a colored image or colored images in the film.

Grams p-Amino-diethylaniline sulfate 2.5

0 Sodium sulfite (anhydrous) 2,

Sodium carbonate (anhydrous) 20 Potassium bromide Water to 1 liter The aromatic amino developing agents used with the coupler compounds of my invention include the alkyl phenylenediamines and alkyl toluenediamines. These compounds are usually used in the form of hydrochloride or the sulfate. Suitable developing agents are diethyl-p-phenylende diamine hydrochloride, monomethyl-pphenylenediamine hydrochloride, dimethyl-pphenylenediamine hydrochloride and 2-amino- 5-diethylamino toluene hydrochloride. The p-aminophenols and their substitution products may also be used where theamino group is unsubstituted. All of these compounds have an unsubstituted amino group which enables the oxidation product of the developer to couple with the color-forming compound to form a dye image.

My development process may be employed for the production of colored photographic images in layers of gelatin or other water-permeable carrier such as collodion organic esters of cellulose or synthetic resins. The carrier may be supported by a transparent material such as glass, a cellulose ester or a non-transparent reflecting material such as paper on an opaque cellulose ester. The emulsion may be coated on the support as a single layer or as a superposed layer on one or both sides of the support.y-'Ihe superposed layers may be differentially sensitized to form a natural color photographic image in the wellknown manner.

The couplersof my invention may be easily prepared from readily available materials and are therefore more economical than many couplers previously described in the art. They have a high degree of solubility in solutions used to disperse them in the emulsion and are more readily dispersible according to the methods of Mannes and Godowsky U. 8. Patent 2,304,940 and Jelley and Vittum U. S,"Patent, 2,322,027 than many couplers hitherto available. They have a higher resistance to crystallization than corresponding couplers containing a'biphenyl group.

All of these advantages make themdesirable couplers for use in color photography;

It will be understood that the examples and compounds set forth herein are illustrative only and that my invention is to be taken aslimited only by the scope of the appended claims.

What I claim is: I I 1. A photographic emulsion for forming colored images, comprising a water-permeable carasu eei .rier containing .a sensitive silver .halide .-and a "coupler .compound containing a reactive group .selected -from the class .consisting of .methylene .and phenolic methenyl groups which are reaccompound having attached thereto in a position other than at said reactive group, a terphenyl radical.

2. ,A photographic emulsion for forming col- :ored*images, comprising a water-permeable carrier containing a "sensitive "silver halide and a coupler compound containing a reactive group selected from the class consisting of methylene and phenolic methenyl "groups which are reactive with the development product of a primary aromatic amino developing agent, said coupler compound having *attached thereto in a position other than at said reactive group, an ortho-terphenyl radical.

'3. A photographic emulsion "for forming colored "images comprising a Water-permeable carrier "containing a sensitive silver halide and coupler compound having the general formula":

CoHs where R is selected from the class consisting of hydrogen and benzoyl.

5. A photographic emulsion for forming colored images, comprising a :gelatino-silver ;halide emulsion containing a coupler compound of the following formula:

where R is selected from the class consisting of ri-o-terphenyl and ,8-[4-(4'-o terphenamido') l 'ph'enethyl radicals.

6. A photographic emulsion for forming colored images, comprising a gelatino silver "halide emulsion containing a coupler compound. oi t following formula:

:12 where 'Rlis a mononuclear aryliradical, and .R'

is a terphenyl radical.

7. '-A photographic emulsion for .forming colored .images, comprising -a gelatino -silver .halide emulsion containinga couplercompoundiof the following formula:

l.8..A photographic emulsion for forming colored-images, comprising .a .gelatino-silver halide emulsion containing a coupler compound .of the following formula:

9. The .method of producing a colored photographic image in a silver "halide emulsion layer, which comprises exposing said layer and developing it with a primary aromatic amino developing agent :in the presence of a coupler compound, containing 'a reactive group selected from the class consisting of methylene and phenolic meth- =enyl-groups-which are reactive with'the develop- .mentiproduct of'a'primary aromatic amino developing agent, said coupler compound having attachedthereto in a position other than at said reactive group, a terphenyl radical.

10. Themethod of "producing a colored photographic image in afsilver halide emulsion layer, which :"comprisesexposing said layer and devel- "oping'it with a primary aromatic amino developing agent-in the presence of a couplercompound havin the following formula:

where R'is 'selectedirom the class consisting of hydrogen and benzoyl.

'11. The methodof producing a colored photographic image in asilver halide emulsion layer, which comprises exposing said layer and developing it with a primary aromatic amino developing agent in the presence of a coupler compound having the .following .formula:

where R is selected from the class consisting of 4-o-terphenyl and fi-[4-(4-o-terphenamido)] phenethyl :radicals.

12. The method of producing a colored photo- -.graphic image in .a silver halid emulsion layer, which comprises exposing said layer and develop- 13 ing it with a primary aromatic amino developing agent in the presence of a coupler compound having the followin formula:

R-COCHzCONH-R where R is a mononuclear aryl radical and R is a terphenyl radical.

CHARLES F. H. ALLEN.

14 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,039,730 Mannes May 5, 1936 2,179,239 Wilmanns Nov. 7, 1939 

1. A PHOTOGRAPHIC EMULSION FOR FORMING COLORED IMAGES, COMPRISING A WATER-PERMEABLE CARRIER CONTAINING A SENSITIVE SILVER HALIDE AND A COUPLER COMPOUND CONTAINING A REACTIVE GROUP SELECTED FROM THE CLASS CONSISTING OF METHYLENE AND PHENOLIC METHENYL GROUPS WHICH ARE REACTIVE WITH THE DEVELOPMENT PRODUCT OF A PRIMARY AROMATIC AMINO DEVELOPING AGENT, SAID COUPLER COMPOUND HAVING ATTACHED THERETO IN A POSITION OTHER THAN AT SAID REACTIVE GROUP, A TERPHENYL RADICAL. 